Following with the advance of technology and progress to the era of information, wireless communication technologies become mature and improved, and it has been applied to various fields to make our life more fruitful and convenient. Among the present wireless communication technologies, radio frequency (RF) wireless technology is the one of most implementation to our daily life.
Among the technological development of RF wireless technology, radio frequency identification (RFID) technology is one of topic has been focused. RFID, also known as e-Tag, is a kind of communication technology featuring the usage of radio-frequency electromagnetic coupling fields to transfer data, for the purposes of identifying the specific objects and read write the data concerned. RFID technology is a wireless non-contact identification technology without the necessity of any mechanical or optical contact. Thus, it has become quite popular and merged in life of everyday.
For example, RFID can be used in manufacturing lines for tracking and controlling the process of manufacture, in order to improve its efficiency. RFID can also be used for helping people to distinguish the real and fake of merchandise. In our daily lives, RFID has been deployed and integrated in various applications such as personal identification of Mass Rapid Transmit system, (MRT) and payment of parking charge and convenient stores, also to those of application which could be simplified and speed up with its transaction and processes.
However, the traditional RFID smart cards are in short of the capability to show the card data, so after haven't use the card for a while, such as the MRT user they cannot make sure how much money was left in the card. If he wants to know the remaining amount in the card, he must find a card reader to check the balance of card. In addition, most of smart cards with display in present are implemented with battery, therefore they cannot be sealed thoroughly. These smart cards are unable to fulfill the requirement of shockproof, shatterproof, waterproof, moisture protection, and last for a long usage time. Thus, there is a motivation of innovation to the existed and traditional smart cards.